I am so surprised that being new to this site but it's the very first one which has in-house fighting among fellow BWM owners, in this case M3 vs 335i.
It's a change for the norm on other sites which is arguments on either BMW vs Audi or BMW vs Mercedes.
Who really cares if a modded 335i is quicker than an M3, all this gets you is bragging rights down at the local pub, it's childish guys. As someone already stated a modded car is always quicker than stock but some people like myself don't want or wouldn't have a modified car for one reason or another and I am happy with my slower but most stylish M3.